I customize in the Editor a level editor for my game, i can serialize all my level data parameters in the level_x file.
I'd like to add an EditorWindow which permit drawing elements, and store in a list in my serialize file below.
I don't know how to link my CustomLevel class (my editor data manager) with an EditorWindow.

I have a solution.
Store a list object in a level_x file works and i can access it from another class using the instance.
My trouble was you can add an element with .add method, you must use insert method, after all list class variable element are stored.

Think I misunderstood you original question, but glad you have a solution. Can be a bit messy working with custom editors, but check out also some of the editor code provided if you see similar behaviour from any of my stuff. Should hopefully be clear enough to read.

At edit time the values should be saved automatically but you might need to use ApplyModifiedProperties or the like. Run time that won't work and so you would need to use some other serialisation method such as saving to json (or possibly the BinaryFormatter).

When is it you need to update the values and how are you trying so far?

I finally understood how it works, i saw a unity video on editor.
I put the correct pattern and it perfectly works.

I try to enhance the customeleveleditor with a graphic level editor to put different gameobject type on the screen.
I'm working too on sequencial level editor (with task & node) to internally manage the level timeline.

I'm not able to industrialize and made it so generic like you, but it can be a roadmap element for you.
I'll send you more information later

ps: you have this error below on your website when we submit after a post reply

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